class Gracenote

# File lib/gracenote.rb, line 18
def initialize (spec)
  if(spec[:clientID].nil? || spec[:clientID] == "") 
    raise "clientID cannot be nil"
  end
  if(spec[:clientTag].nil? || spec[:clientTag] == "")
    raise "clientTag cannot be nil"
  end
  
  @clientID = spec[:clientID]
  @clientTag = spec[:clientTag]
  @userID = spec[:userID].nil? ? nil : spec[:userID]
  @apiURL = "https://c" + @clientID + ".web.cddbp.net/webapi/xml/1.0/"
end

# File lib/gracenote.rb, line 100
def albumToc(toc)
  if @userID == nil 
    registerUser
  end
  body = "<TOC><OFFSETS>" + toc + "</OFFSETS></TOC>"
  data = constructAlbumQueryBody(body, "ALBUM_TOC")
  return parseAlbumRES(data)
end

# File lib/gracenote.rb, line 209
def fetchContributor (gn_id)
  if @userID == nil 
    registerUser
  end

  body = "<GN_ID>" + gn_id + "</GN_ID>
          <OPTION>
            <PARAMETER>SELECT_EXTENDED</PARAMETER>
            <VALUE>IMAGE,MEDIAGRAPHY_IMAGES</VALUE>
          </OPTION>"

  data = constructQueryReq(body, "CONTRIBUTOR_FETCH")

  resp = api(data)
  return checkRES(resp)
end

# File lib/gracenote.rb, line 113
def fetchOETData(gn_id)
  if @userID == nil 
    registerUser
  end

  body = "<GN_ID>" + gn_id + "</GN_ID>
            <OPTION>
              <PARAMETER>SELECT_EXTENDED</PARAMETER>
                <VALUE>ARTIST_OET</VALUE>
            </OPTION>
            <OPTION>
              <PARAMETER>SELECT_DETAIL</PARAMETER>
                <VALUE>ARTIST_ORIGIN:4LEVEL,ARTIST_ERA:2LEVEL,ARTIST_TYPE:2LEVEL</VALUE>
            </OPTION>"

  data = constructQueryReq(body, "ALBUM_FETCH")
  resp = api(data)
  resp = checkRES resp
  
  json = resp["RESPONSES"]

  output = Array.new()
  output[:artist_origin] = json["RESPONSE"]["ALBUM"]["ARTIST_ORIGIN"].nil? ? "" : _getOETElem(json["RESPONSE"]["ALBUM"]["ARTIST_ORIGIN"]) 
  output[:artist_era]    = json["RESPONSE"]["ALBUM"]["ARTIST_ERA"].nil? ? "" : _getOETElem(json["RESPONSE"]["ALBUM"]["ARTIST_ERA"])
  output[:artist_type]   = json["RESPONSE"]["ALBUM"]["ARTIST_TYPE"].nil? ? "" : _getOETElem(json["RESPONSE"]["ALBUM"]["ARTIST_TYPE"])
  return output
end

# File lib/gracenote.rb, line 147
def fetchSeason (gn_id)
  if @userID == nil 
    registerUser
  end

  body = "<GN_ID>" + gn_id + "</GN_ID>"
  data = constructQueryReq(body, "SEASON_FETCH")

  resp = api(data)
  return checkRES(resp)
end

# File lib/gracenote.rb, line 163
def fetchTVShow (gn_id)
  if @userID == nil 
    registerUser
  end

  body = "<GN_ID>" + gn_id + "</GN_ID>
            <OPTION>
              <PARAMETER>SELECT_EXTENDED</PARAMETER>
              <VALUE>IMAGE</VALUE>
            </OPTION>"

  data = constructQueryReq(body, "SERIES_FETCH")

  resp = api(data)
  return checkRES(resp)
end

# File lib/gracenote.rb, line 92
def findAlbum(artistName, albumTitle, matchMode = @@ALL_RESULTS)
  return findTrack(artistName, albumTitle, "", matchMode)
end

# File lib/gracenote.rb, line 81
def findArtist(artistName, matchMode = @@ALL_RESULTS)
  return findTrack(artistName, "", "", matchMode)
end

# File lib/gracenote.rb, line 230
def findContributor (name)
  if @userID == nil 
    registerUser
  end

  body = "<TEXT TYPE='NAME'>" + name + "</TEXT>
            <MODE>SINGLE_BEST</MODE>
          <OPTION>
            <PARAMETER>SELECT_EXTENDED</PARAMETER>
            <VALUE>IMAGE,MEDIAGRAPHY_IMAGES</VALUE>
          </OPTION>"

  data = constructQueryReq(body, "CONTRIBUTOR_SEARCH")
  
  resp = api(data)
  return checkRES(resp)
end

# File lib/gracenote.rb, line 185
def findTVShow (name, single=true)
  if @userID == nil 
    registerUser
  end

  singleText = single ? '<MODE>SINGLE_BEST</MODE>' : ''

  body = "<TEXT TYPE='TITLE'>" + name + "</TEXT>
          " + singleText + "
          <OPTION>
            <PARAMETER>SELECT_EXTENDED</PARAMETER>
            <VALUE>IMAGE</VALUE>
          </OPTION>"

  data = constructQueryReq(body, "SERIES_SEARCH")

  resp = api(data)
  return checkRES(resp)
end

# File lib/gracenote.rb, line 67
def findTrack(artistName, albumTitle, trackTitle, matchMode = @@ALL_RESULTS)
  if @userID == nil 
    registerUser
  end
  body = constructAlbumQueryBody(artistName, albumTitle, trackTitle, "", "ALBUM_SEARCH", matchMode)
  data = api(constructQueryReq(body))
  return parseAlbumRES(data);
end

# File lib/gracenote.rb, line 37
def registerUser (clientID = nil)
  if(clientID.nil?)
    clientID = @clientID + "-" + @clientTag
  end
  
  if not @userID.nil?
    puts "user already registered. No need to register again"
    return @userID
  end

  #send req to server and get user ID
  data =  "<QUERIES>
            <QUERY CMD='REGISTER'>
              <CLIENT>"+ clientID +"</CLIENT>
            </QUERY>
          </QUERIES>"
  resp = api(data)
  resp = checkRES resp
  @userID = resp['RESPONSES']['RESPONSE']['USER']

  return @userID
end

# File lib/gracenote.rb, line 458
def _getAttribElem(data, attribute, value)
  data.each do |g|
    attrib = Rack::Utils.parse_query URI(g).query
    if(attrib[attribute] == value) 
      return g
    end
  end
end

# File lib/gracenote.rb, line 471
def _getOETElem (data)
  output = Array.new()
  input = Array.new()
  if data.class.to_s != 'Array'
    input.push data
  else 
    input = data
  end
  input.each do |g|
    output.push({:id => g["ID"].to_i, :text => g})
  end
  return output
end

# File lib/gracenote.rb, line 254
def api (query)
  return Gracenote::HTTP.post(@apiURL, query)
end

# File lib/gracenote.rb, line 333
def checkRES resp
  if resp.code.to_s != '200'
    raise "Problem!! Got #{resp.code} with #{resp.message}"
  end
  json = nil
  begin
    json = Crack::XML.parse resp.body
  rescue Exception => e
    raise e
  end

  status = json['RESPONSES']['RESPONSE']['STATUS'].to_s
  case status
    when "ERROR"
      raise "ERROR in response"
    when "NO_MATCH"
      raise "No match found"
    else
      if status != "OK"
        raise "Problems found in the response"
      end
   end 
  return json
end

# File lib/gracenote.rb, line 285
def constructAlbumQueryBody(artist, album, track, gn_id, command = "ALBUM_SEARCH", matchMode = @@ALL_RESULTS)
  body = ""
  # If a fetch scenario, user the Gracenote ID.
  if command == "ALBUM_FETCH"
          body += "<GN_ID>" + gn_id + "</GN_ID>"
  else
    # Otherwise, just do a search.
    # Only get the single best match if that's what the user wants.
    if matchMode == @@BEST_MATCH_ONLY
      body += "<MODE>SINGLE_BEST_COVER</MODE>" 
    end
    # If a search scenario, then need the text input
    if artist != "" 
      body += "<TEXT TYPE=\"ARTIST\">" + artist + "</TEXT>"
    end
    if track != "" 
      body += "<TEXT TYPE=\"TRACK_TITLE\">" + track + "</TEXT>"
    end
    if album != "" 
      body += "<TEXT TYPE=\"ALBUM_TITLE\">" + album + "</TEXT>"
    end
  end
  # Include extended data.
  
  body += "<OPTION>
            <PARAMETER>SELECT_EXTENDED</PARAMETER>
            <VALUE>COVER,REVIEW,ARTIST_BIOGRAPHY,ARTIST_IMAGE,ARTIST_OET,MOOD,TEMPO</VALUE>
          </OPTION>"

  # Include more detailed responses.
  body += "<OPTION>
            <PARAMETER>SELECT_DETAIL</PARAMETER>
            <VALUE>GENRE:3LEVEL,MOOD:2LEVEL,TEMPO:3LEVEL,ARTIST_ORIGIN:4LEVEL,ARTIST_ERA:2LEVEL,ARTIST_TYPE:2LEVEL</VALUE>
          </OPTION>"

  # Only want the thumbnail cover art for now (LARGE,XLARGE,SMALL,MEDIUM,THUMBNAIL)
  body += "<OPTION>
            <PARAMETER>COVER_SIZE</PARAMETER>
            <VALUE>MEDIUM</VALUE>
          </OPTION>"

  return body
end

# File lib/gracenote.rb, line 263
def constructQueryReq(body, command = "ALBUM_SEARCH")
  #construct the XML query
  return  "<QUERIES>
              <AUTH>
                  <CLIENT>"+ @clientID + "-" + @clientTag + "</CLIENT>
                  <USER>"+ @userID + "</USER>
              </AUTH>
              <QUERY CMD=\"" + command + "\">
                  " + body + "
              </QUERY>
          </QUERIES>"
end

# File lib/gracenote.rb, line 448
def merge_recursively(a, b)
  a.merge(b) {|key, a_item, b_item| merge_recursively(a_item, b_item) }
end

# File lib/gracenote.rb, line 362
def parseAlbumRES resp
  json = nil
  begin
    json = checkRES resp
  rescue Exception => e
    raise e
  end
  output = Array.new
  data = Array.new
  if json['RESPONSES']['RESPONSE']['ALBUM'].class.to_s != 'Array'
    data.push json['RESPONSES']['RESPONSE']['ALBUM']
  else 
    data = json['RESPONSES']['RESPONSE']['ALBUM']
  end
  
  data.each do |a|
    obj = Hash.new 
    
    obj[:album_gnid]         = a["GN_ID"].to_i
    obj[:album_artist_name]  = a["ARTIST"].to_s
    obj[:album_title]        = a["TITLE"].to_s
    obj[:album_year]         = a["DATE"].to_s
    obj[:genre]              = _getOETElem(a["GENRE"])
    obj[:album_art_url]      = _getAttribElem(a["URL"], "TYPE", "COVERART")

    # Artist metadata
    obj[:artist_image_url]  = _getAttribElem(a["URL"], "TYPE", "ARTIST_IMAGE")
    obj[:artist_bio_url]    = _getAttribElem(a["URL"], "TYPE", "ARTIST_BIOGRAPHY")
    obj[:review_url]        = _getAttribElem(a["URL"], "TYPE", "REVIEW")

    # If we have artist OET info, use it.
    if not a["ARTIST_ORIGIN"].nil?
      obj[:artist_era]    = _getOETElem(a["ARTIST_ERA"])
      obj[:artist_type]   = _getOETElem(a["ARTIST_TYPE"])
      obj[:artist_origin] = _getOETElem(a["ARTIST_ORIGIN"])
    else
    # If not available, do a fetch to try and get it instead.
      obj = merge_recursively(obj, fetchOETData(a["GN_ID"]) )
    end

    # Parse track metadata if there is any.
    obj[:tracks] = Array.new()
    tracks = Array.new()
    if a["TRACK"].class.to_s != 'Array'
      tracks.push a["TRACK"]
    else 
      tracks = a["TRACK"]
    end
    tracks.each do |t|
      track = Hash.new()

      track[:track_number]      = t["TRACK_NUM"].to_s
      track[:track_gnid]        = t["GN_ID"].to_s
      track[:track_title]       = t["TITLE"].to_s
      track[:track_artist_name] = t["ARTIST"].to_s

      # If no specific track artist, use the album one.
      if t["ARTIST"].nil? 
        track[:track_artist_name] = obj[:album_artist_name]
      end
      
      track[:mood]              = _getOETElem(t["MOOD"])
      track[:tempo]             = _getOETElem(t["TEMPO"])

      # If track level GOET data exists, overwrite metadata from album.
      if not t["GENRE"].nil? 
        obj[:genre]         = _getOETElem(t["GENRE"])
      end
      if not t["ARTIST_ERA"].nil?
        obj[:artist_era]    = _getOETElem(t["ARTIST_ERA"])
      end
      if not t["ARTIST_TYPE"].nil?
        obj[:artist_type]   = _getOETElem(t["ARTIST_TYPE"])
      end
      if not t["ARTIST_ORIGIN"].nil?
        obj[:artist_origin] = _getOETElem(t["ARTIST_ORIGIN"])
      end
      obj[:tracks].push track
    end
    output.push obj
  end
  return output
end